SRL Service Manual
Revision 00
July 2007
Page 30 of 56
7. Operation & Control
7.1 Turning the Dryer On or Off
Turn the main switch to the “I/ON” position.
For the first few seconds, the controller does an internal check, during which time the
display shows “d.t.3”, indicating the version of the software installed.
The dryer then can be in one of three operating modes:
•
OFF
: The display is off. The “Power” light is yellow. Al other lights are off.
•
ON:
The display shows the reading of dew point sensor (B1). The “power” light is green.
All other lights are off, lighting up only when: a) an alarm or warning occurs, b) the drain
valve is activated, or c) the refrigerant compressor cycls off.
•
Remote OFF:
In this case the dryer has been turned off remotely. The
display shows “r.OF”. The “Power” light is yellow. Al other lights are off.
Note: The Remote OFF function can be activated by replacing the bridge between
terminals X4.0 and X4.10 in the electrical cabinet with a switch. With the contact open, the
remote OFF is activated (dryer is turned off), with the contact closed, it is not activated
(dryer is turned on).
To turn the dryer ON, press the ON/OFF button (or provide the command via an external control
system as described above). The display will show the B1 (dewpoint temperature) sensor reading and
the refrigerant compressor will turn on*.
To turn the dryer OFF, press the ON/OFF button or provide the command via an external control
system. The display goes off, and the refrigerant compressor stops.
The dryer can also be turned OFF remotely by opening the Remote OFF Contacts as described
previously. In this case the compressor stops and “r.OF” is displayed. Note that the On/OFF switch
must be in the On position in order to activate the Remote Off Mode.
When in remote OFF, closing the Remote Off Contacts turns the dryer on. The
compressor comes on* and the display blinks “on” for 5 seconds and then displays the
B1 dewpoint temperature reading.
The dryer status is recorded in the flash memory of the controller, so disconnecting power to the unit
while it is on will cause the dryer to automatically come back on 5 seconds after the power is restored.
If during these 5 seconds the ON/OFF button is pressed or an off command is coming through the
external control system, the controller stays off.
* If the evaporator temperature is below the cycling set point, the refrigerant compressor will remain off
and the “Energy Saving” light will come on.